We you want to point out in advance that a HomePod or a stereo pair can not replace a real home theater system. In addition to the lack of spatial sound, the HomePod can not implement the well-known audio technology such as Dolby Atmos. In addition, only two speakers can currently be connected to each other. However, Apple could provide support for surround playback with multiple HomePod speakers. If you currently have no Surroud system, then the Apple speaker is a good alternative.
How to Connect the HomePod to an Apple TV
The easiest way to set the HomePod as the speaker for your Apple TV is via the Home screen. Hold down the Play button on your Siri Remote. After a short time you will see different audio options. Simply select the HomePod and it will be set as the output device.
Alternatively, you can change the audio device while playing a video or song. To do this, swipe from top to bottom on your Siri Remote on the touch panel. Now select "Audio". In addition to language options and volume control settings, you can select the HomePod as the playback device on the right.
The third and last option is to set the HomePod as output device via the settings menu. To do this, open the Settings app on the Home screen and then select the "Video and Audio" entry. Then click on the option "Audio output". Select the HomePod from the list of possible audio devices and then press the menu button on the Siri Remote to apply the setting.
Watch out for videos
Please note that there is a delay when using the HomePod as a speaker. When playing music, this is of course negligible, but in movies and series, this can affect the synchronicity of image and sound.